One may be more restrictive than the other to the point that even though it drop temps more it still doesn't result in the most overall power. You also have to imagine that the more restrictive intercoolers may exchange heat better because they are slowing the air down and keeping it in the intercooler longer. The less restictive ones just let the air pass on by without having as much thermal effect on it. What you are looking for is the right balance, which in our mind is the intercooler that makes the most peak power. We think we have that.